#compdef od

local context state state_descr line args ret=1
local -A opt_args

args=(
  '(-A --address-radix)'{-A+,--address-radix=}'[file offset base]:base:((d\:decimal o\:octal x\:hexadecimal n\:none))'
  '(-j --skip-bytes)'{-j+,--skip-bytes=}'[skip specified bytes]:bytes'
  '(-N --read-bytes)'{-N+,--read-bytes=}'[dump at most specified bytes]:bytes'
  '*'{-t+,--format=}'[specify output format]:format string:->format'
  '(-v --output-duplicates)'{-v,--output-duplicates}'[do not use * to mark line suppression]'
  '-a[output named characters (-t a)]'
  '-b[output octal bytes (-t o1)]'
  '-c[output characters with C-style escape (-t c)]'
  '-d[output unsigned decimal shorts (-t u2)]'
  '-f[output single-precision floats (-t fF)]'
  {-h,-x}'[output hexadecimal shorts (-t x2)]'
  '-i[output decimal integers (-t dI)]'
  {-l,-I,-L}'[output decimal longs (-t dL)]'
  {-o,-B}'[output octal shorts (-t o2)]'
  '-s[output decimal shorts (-t d2)]'
  '*:files:_files'
)

if _pick_variant gnu=GNU unix --version; then
  # -h -B -I and -L are obsolescent and undocumented
  args=( ${(R)args:#(|\*)(|\(*\))-[hBIL]*} )
  args+=(
    {-S+,--strings=-}'[output strings of at least specfied bytes long]:length'
    {-w-,--width=-}'[output specified bytes per line]:bytes'
    '(- : *)--help[display help and exit]'
    '(- : *)--version[output version information and exit]'
  )
else
  args=( ${(R)args:#(|\*)(|\(*\))--*} )    # remove long options
  case "$OSTYPE" in
    (darwin*|freebsd*|dragonfly*|openbsd*)
      args+=(
        '-D[output unsigned decimal ints (-t u4)]'
        {-e,-F}'[output double-precision floats (-t fD)]'
        {-H,-X}'[output hexadecimal ints (-t x4)]'
        '-O[output octal ints (-t o4)]'
      )
      ;;
    (*)
      # POSIX options only
      args=( ${(M)args:#(|\*)(|\(*\))-[AjNtvbcdosx]*} )
      ;;
  esac
fi

_arguments -s -S : "$args[@]" && return 0

case "$state" in
  (format)
    compset -P '*[acCSIL1248FDL]'
    if compset -P '*[doux]'; then
      args=( 'C:char' 'S:short' 'I:int' 'L:long' 1 2 4 8 )
      _describe -t integer-size 'size of integer' args && ret=0
    elif compset -P '*f'; then
      args=( 'F:float' 'D:double' 'L:long double' )
      _describe -t float-size 'size of float' args && ret=0
    fi
    args=( 'a:named character' 'c:character (C-style escape)'
           'd:decimal' 'o:octal' 'u:unsigned decimal'
           'x:hexadecimal' 'f:floating-point number' )
    _describe -t type-specifier 'type specifier' args && ret=0
  ;;
esac

return ret